Modern medical practice utilizes a variety of fluid pumps for diverse applications such as introducing a saline solution into patients to maintain hydration and supplying patient controlled anesthesia. Because of the variety of applications for these pumps, they employ widely different flow rates ranging from a fraction of a milliliter per hour to several liters/hour. Presently devices which measure the flow and volume output of pumps do so by passing the pump fluidic output into a transparent tube and introducing bubbles into the tube. Measurements of flow and volumetric output may be derived by measuring the time required for the bubbles to move past multiple fixed optical sensors. Devices embodying such means of flow measurement are of limited utility for timely measurements because, at low flow rates, a derived flow measurement may require several minutes, several hours, or may require several tens of hours for the bubbles under test to move between points along an array of multiple fixed optical sensors.